Reliability of center of pressure measures for assessing the development of sitting postural control through the stages of sitting.

This was a re-analysis of previously published data, not a new prospective measurement trial. The sample was small and uneven: 33 typically developing children and 26 children with or at risk for cerebral palsy, of whom 16 had a diagnosis. The children with or at risk for cerebral palsy included those classified at GMFCS levels 1 to 4, so the group was not homogeneous. The children were recruited from employee announcements at local universities, so they may not represent a typical clinic population. Data collection required three acceptable independent sitting trials, and sessions stopped if the child could not complete them, so the findings may not apply to infants who cannot sustain sitting for testing. Consistency values varied widely, from poor to excellent, so no single center-of-pressure measure can be treated as dependable. The study did not show that assessing by sitting stage was more reliable than assessing across sessions. The study assessed measurement consistency, not treatment effect.

The authors declared no known conflicts of interest and said there was no significant financial support that could have influenced the outcome.

Do not treat these body sway measures as a ready-made outcome test. Many values were poor or fair to good, and the study did not show that stage-based testing was better than repeated sessions.